Can you tell the age of a salmon by the number of scales it has?

No, you cannot determine the age of a salmon just by counting its scales. While the number of scales on a salmon does increase as it grows older, other factors can influence the scale count. Additionally, the scales of a salmon fall off as it moves upstream to spawn, so the scale count may not accurately reflect its age.

Scientists use other methods to determine the age of salmon, such as examining the growth rings on their otoliths (ear bones), which provide more accurate results. The otoliths contain distinct rings, much like tree rings, that can be counted to estimate the age of the salmon. Other methods include analyzing the scale patterns and growth rates, as well as the presence of certain chemical markers that change as the salmon ages.